Bone vs. Titanium: Are Wider Implants Justified?

The recommendation for the widest implants possible was likely made by engineers who assume that screwing an implant into viable bone is the same as screwing an implant into wood. The consensus appears to be that a minimum of 2mm bone thickness should remain between the rim of an implant and the edge of the crest. Much closer and one risks resorption, with the gingival level headed south. This is due to any number of factors, including biologic remodeling around the implant/abutment interface as well as obliteration of blood supply by an overly wide implant.

I would agree that fatter trumps longer but, not at the expense of a foundation with which to hold in the implant.

There is logic behind both sides and you need to apply sound biological and mechanical principles to get the excellent outcomes that you want. The reason for wider diameters was originally based on surface area of the implant available for osseointegration, with shorter but wider implants having the greater surface area. The additional indications were for better ability to support the functional loads on the molar regions and for biomimetics to better resemble the naturally wide shape and emergence of molars in the posterior region. That said, it is also important to fit the size of the implant to the available bone or to modify the existing bone to the recommended width and height to fit the desired implant. Many failures of wide diameter implants occured during their introduction due to them being placed in bone that was not wide enough to support them. One more thing. Just because textbooks recommend wider diameters in the posterior regions, does not mean that a well placed regular diameter implant, will not be successful there also. I have many patients with regular diameter external hex implants (popular at the time)in the molar regions that are doing very well after 10 and 15 years of function.

Dear Dr. IR: So far, every comment on your question, including the lecturer you were listening to has been right on. Enough healthy, vascular bone surrounding an implant is necessary for long term success of that implant (among a host of other criteria, not the least of which would be occlusion, tissue maintenance and support, etc)... but I digress... This doesn't mean, however, that wider implants are not an invaluable tool to pull out of you tool box should the need, opportunity and/or case arise. I personally have utilized every implant width (and I mean EVERY, from the slimmest 1.8mm Imtecs to the widest 9mm Southern Max Implants and every diameter in between ) to fit the clinical situation to provide the ideal long term support, cleansibility, cosmetic profile, etc. I do believe that if we are "fitting the patient to the implant" (ie the one we happen to have on-hand) instead of the other way around, we are doing the patient a disservice.

Dear colleague; Implantology is a new course w/ a lot of controversies,so far what is accepted now is to place wide implant in molar areas. Every implant size should obey the size of the missing tooth w/c is going to be replaced,that's what I believe,and in posterior area if 2 teeth are being replaced, w/ bone defficiency, i'd rather place regular ones and splint them, and in my practice they are all successfull. BUT in single tooth replacements, I follow the text to place the wide implant, and augment the bone if needed.

Doctors What about the restorative factor platform size. Remember, we are doing this for the prosthetics and the smaller the connection, the weaker the connection in hygenic capacity and also torque capacity. It not just about the surgical aspect, its about the top part. Thats why we do implants. It must last, be easy to clean for the patient, and cost effective.

Hi, in my opinion ,choose wide or regular is depended ,the location ,number and masticatory force(opposite jaw).and u need to have 1.5 cancellos bone around thefixture,if u don,t have ,u can do spreading ,comrehensive techniqe or bonegraft before placing fixture. , marzbani ,iran

i have been receiving this forum by email for a while, but have not had time to really delve into it.... i started today and i think it is SO wonderful to have a forum like this where " wet gloved " ( use to be wet finged )Dentists from all over can exchange ideas and experiences..... Drs. marzbani and danesh....is there an active, modern Dental field....in IRAN??? i am so surprized to hear that..... How can i find out more about that?? to all the Docs.....thanks for all your input....i am sure this site will be fun and informative!!! Marshall S. Dicker DMD FAGD

Over a period of time keeping in mind that 2mm of bone has to be preserved all around you feel more confident with as wider implants.This is true more so when you are placing immediate implants.

It seems the best result is to use as little as possible and let the natural health of the mouth, bones and gums take over.

@Marshall S. Dicker DMD FAGD: I love your suprise at there being an active modern dental scene in Iran. It gives the humorous impression that Iran is perhaps living in the dark ages, perhaps some laws certainly give that impressions. However, should you ever visit the country its in starke contrast to the largely governmental driven properganada news that's peddled throughout most of the Western world. Dental work is of high quality, equally there's a huge cosmetic surgery scene and with nose jobs being the most popular type of cosmetic surgery, perhaps ironically, this trend is inspired by Hollywood.

I have to agree,JonH. One cannot help but smile at the candor his surprise had created ! I truly feel that it is the diversity of cultures that make this website truly fascinating, not to mention the magnitude of information being processed, and the clash of egos being generated with passion. Hopefully, as we interact and learn more of other cultures, we can attain and promote better understanding and acceptance of each others' differences. Warmest regards,

"Wolff's law" states that bone models and remodels in response to the mechanical stresses it experiences so as to produce a minimal-weight structure that is 'adapted' to its applied stresses. The behaviour of bone according to Wolff's law mirrors a fundamental trait of mother nature, i.e. optimal economic use of substance in the performance of a function. Thus to use a wide diameter implant because there is a wide hole seems to contradict this fundamental. A living organism deserves to be treated according to living rules of life, not static non-living engineering presumptions. Granted that we need to use a titanium screw, since the tooth germ implant is not yet available..... it does make more organic living sense to use the optimal titanium necessary to allow maximal living tissue around it and thus also minimize the perio pocket that inevitably forms around all dental implants. Minimized and optimized diameter implants should be the trend and not large diameter dental implants. If we have to put something foreign into the living body, put in the smallest you can. That is what the "GREEN MOVEMENT" is all about...... to use just enough and leave the rest alone and we will save the world ! After all, are we not living in the narrow sweet zone between bleeding to death and clotting to death. And if our beloved earth is 10,000 Km nearer or further from the sun, we will either burn or freeze. Just enough is the way to go.

I placed Southern Implants 8 and 9 mm wide implants ,I have found them to be very technique sensitive and un- forgiving ,concerning depth of placement and thickness of bone and soft tissue biotype. They need more scientific validation and prospective clinical studies (at least 3-5 years results). The representatives were no help either. I am sticking to what I know and what always worked. The only thing I may try new is from a company like Nobel that has been around long enough and has two legs to stand on.

The increased failure rate of ultra-wide implants is related less to the implant diameter than it is to the quality of bone into which it is placed. There is a reason why the literature states that there should be a minimum of 2mm of bone on the facial and palatal walls of ridges. Medullary bone has high cellularity and lower inorganic component. Cortical bone has a very high inorganic component and poor cellularity. Placed in medullary bone, implants are adjacent to cells necessary for integration. As you encroach on the cortical zone, a large part of the surface area of these types of implants are in contact with cortical bone. These cortical plates tend to go through a process of resorption rather than maintenance at the implant interface; the net result is dehiscence and implant loss. The selection of implant diameter should reflect the cortical/medullary zones rather than ridge width alone. RJM

Dr. Miller: Well stated, good job.